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Discussion Starter #1
This is for a '95 GL Sedan;

Here's the problem and what I've done so far;
The brake lights don't work at all, and they went out very suddenly. I saw them working just a few days ago when my wife was pulling the car into the driveway. Everything else in the car works AFAIK, it's just the brake lights. I noticed a few days ago that 1 of the bulbs was not lit, so the 1st thing I did was put 4 new bulbs in.

Checked the fuse under the dash and it tested good. I cleaned the tabs on the fuse just for good measure before putting it back. Still no brake lights.

Checked the switch at the pedal with an ohm meter, tested OK.

Checked for voltage at the switch and it reads 12.5v. While the connector was off I jumpered the wires to simulate the switch on, still no lights.

Visually checked the wiring from the switch to the point I can no longer see it behind the dash and didn't see anything unusual.

Visually checked the wiring from the tail light housings into the trunk as far forward as the rear seat, and again nothing seemed unusual.

I'm thinking at this point there might be a ground wire specific to just the brake lights, separate from the main harness ground. Does anyone know if that's the case? If it is, where is that wire located?
 

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Is there 12V+ at the bulb socket when the brake switch is jumpered?
 

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Discussion Starter #3
I haven't tested that with a meter. I was assuming not since I have all brand new bulbs and they aren't lighting. With a known good bulb, and voltage at the socket, I was thinking the bulb would light, but then thought of the ground wire and hoped I could find that easily if someone here could point me in the right direction for where to look. I should probably check for + volts in one the socket to verify if it is a ground issue, but I'd still ike to know where to check for the ground wire to make sure it's a clean connection.
 

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Make sure the known good bulb is good by testing it across the base pins with an ohm meter.
 

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Do the rear turn signals work? If they do then the ground, bulbs and sockets are OK.

The ground is near the center of the trunk by the latch.
 

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Discussion Starter #6
Yes, turn signals and tail lights work, just no brake lights.

Here's what I did today;

Found the ground wire in the trunk and it looks good.

Tested one of the sockets with my meter, ground tab in the socket is good reading 0 ohms to the car body, however I had no volts at the + tab. I checked the tab in the socket for the tail lights to make sure I was hitting the tabs with the probes at the right place and it showed 12.4v. I double checked for volts at the fuse and the pedal switch to make sure I wasn't overlooking something simple and everything checked out same as yesterday.

So, I'm concluding from todays efforts that the ground isn't the issue, there has to be a break in the + circuit somewhere between the pedal and the rear of the car. When I was checking the switch I noticed the hot wire there was green with a red stripe, but at the socket it's just red and black wires. Where in the car does the wire change from the green/red?

Also, I'm wondering if maybe there's some sort of accessory module that the brake light wire goes to before getting to the light bulbs. I have no idea if this car has ABS, but that's the only type of module I can think of that might tie into the brake light wiring. Can anyone tell me if and where I'd find a module like that in the car? I did see a black box mounted behind the rear seat, but ran out of time before having to go to work so I didn't get a chance to see if there were any loose wires on it, or if any of the wires went to the brake lights.
 

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If you look a the WD you will see a splice or two in the wiring. Wring goes down the drivers side door molding and under the passenger side rear seat.
 

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One bulb to my 3rd brake light sometimes works and sometimes it doesn't because the wiring is loose causing a bad connection.
 

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Discussion Starter #9
Still no brake lights. I have to get this fixed today. One thing seems strange to me, I was checking the wires at the switch with a meter and noticed that the green/red wire has + volts, the other wire is solid green and goes direct to ground. Is that right? I thought if the switch is in the + side of the circuit, then one wire should read nothing, no volts and not grounded either. Does this mean the wiring is shorted? Also, a wire color chart I found online shows the brake light wire for '95 is red with a green stripe, but as I mentioned the wire at the switch is green with a red stripe. I'm confused and frustrated, electrical is really not my forte and I'm out of ideas short of just running a new wire directly from the pedal to the lights. I really don't like that idea because if it's a short causing the problem running a new wire may send volts to the short from both sides of the circuit and start popping fuses. I think my next step is to locate a detailed schematic at the library so I can figure out how this thing is supposed to be wired.
 
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